How much water must be added to 200 gallons of mixture which is 80 percent alcohol to reduce it to a 75 percent mixture?

Question

2939 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2017-04-15T04:19:10

#13 1/3# gallons of water must be added to reduce it to a #75# percent mixture.

#200# gallons of mixture which has #80%# alcohol, has

#200×80%=200×80/100=2×80=160# gallons of alcohol.

If #160# gallons of alcohol forms #75%# of solution, the solutions has to be

#160×100/75=160×4/3=640/3=213 1/3# gallons.

Hence, #213 1/3-200=13 1/3# gallons of water must be added to reduce it to a #75# percent mixture.